Think about it: when someone hugs you, it lasts about three seconds. If they hold on longer, you know something else is going on, like a child not wanting to go to sleep at bedtime, or a lover craving closeness. A study of Olympic athletes congratulating each other confirms the three-second rule. But it's not just a rule for hugs -almost everything we do happens in three-second durations!

Crosscultural studies dating back to 1911 have shown that people tend to operate in 3-second bursts. Goodbye waves, musical phrases, and infants' bouts of babbling and gesturing all last about 3 seconds. Many basic physiological events, such as relaxed breathing and certain nervous system functions do, too. And several other species of mammals and birds follow the general rule in their body-movement patterns. A 1994 study of giraffes, okapis, roe deer, raccoons, pandas, and kangaroos living in zoos, for example, found that although the duration of the animals' every move, from chewing to defecating, varied considerably, the average was, you guessed it, 3 seconds.

"What we have is very broad research showing that we experience the world in about these 3-second time frames," says developmental psychologist Emese Nagy of the University of Dundee in the United Kingdom.

The Olympic hugging study was produced by watching videotapes of televised athletes. They tended to hug their coaches a bit longer than three seconds, their opponents for a bit less, but they averaged out at, yes, three seconds. Link -via J-Walk Blog

I see a flaw here in that they sampled a bunch of different events, the averaged the timespan of all of them to come up with 3 seconds. There's no significance to 3 seconds other than that's where they all statistically gather.

I could average a lot of different events but that wouldn't necessarily tell me anything important about them.

Think about it: when was the last time you shook someone's hand for a whole three seconds? Time it out- that's a long time. If the handshake- one of the most basic forms of social interaction- doesn't conform to the three second rule, then I have to doubt the viability of this report.

Plus, as a professional composer for 20 years I can tell you that most musical phrases are emphatically NOT three seconds long. Again, this makes me doubt the whole report.